ACTG 316 is an international, Phase III study evaluating nevirapine for the prevention of maternal-fetal transmission of HIV. Patient enrollment into this study is ongoing. A total of approximately 1100 enrollments have occurred (>500 mother-infant pairs) out of a target enrollment of 800 in the U.S. and 1244 world-wide. Enrollment will probably continue until late 2001. No complications have been encountered. No preliminary efficacy data are yet available.